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以硅酸钠和氯化钴为原料、十六烷基三甲基溴化铵为模板剂,采用微波辐照法合成4种不同钴含量的含钴介孔分子筛(cobalt-containing mesoporous molecular sieves,Co-MCM-41)。用X射线粉末衍射仪、Fourier变换红外分析、程序升温还原分析、透射电子显微镜、比表面积和孔径测定仪等表征样品的物理化学性能,并研究了合成的Co-MCM-41的稳定性。结果表明:在摩尔比n(SiO_2):n(CoO)=1.0:0.05～1.0:0.2的范围内都可以合成出有序性好的Co-MCM-41。随着Co添加量的增加,Co-MCM-41的比表面积减小,但孔径略有增加,所合成的Co-MCM-41经750℃焙烧3h后仍然具有介孔结构;但是,850℃焙烧3h后,其介孔结构被破坏:100℃水热处理5d后,Co-MCM-41仍然具有介孔结构,样品的比表面积降低很多,并且呈现出虫蛀状介孔结构。
Using sodium silicate and cobalt chloride as raw materials, cetyltrimethylammonium bromide as templating agent, four different cobalt-containing mesoporous molecular sieves (cobalt-containing mesoporous molecular sieves, Co-MCM-41). The physicochemical properties of the samples were characterized by X-ray powder diffraction, Fourier transform infrared spectroscopy, temperature-programmed reduction analysis, transmission electron microscopy, specific surface area and pore size analyzer. The stability of the synthesized Co-MCM-41 was also studied. The results show that the ordered Co-MCM-41 can be synthesized in the molar ratio of n (SiO 2): n (CoO) = 1.0: 0.05 to 1.0: 0.2. With the addition of Co, the specific surface area of Co-MCM-41 decreased, but the pore size increased slightly. The synthesized Co-MCM-41 still possessed mesoporous structure after being calcined at 750 ℃ for 3h. However, calcination at 850 ℃ After 3h, the mesopore structure was destroyed. After hydrothermal treatment at 100 ℃ for 5d, the mesoporous structure of Co-MCM-41 still remained. The specific surface area of the sample decreased a lot and mesoporous mesoporous structure appeared.